Where information associated with various bills derived from business activities are processed by an electronic computer, bill items showing, for example, bill forms such as a debit note or delivery notice, date, buyer code, responsible sales clerk code, bill number, code of a responsible purchase clerk, and code of a buyer's district are regarded as constituent items of a piece of information represented by one heading designation. The quantities, unit prices and total sales amounts of the respective articles are added as detail information groups for each article term to the common bill items of the heading information.
Where the above-mentioned information is processed by, for example, the prior art electronic computer, each detail information group has to be processed, making it necessary to store all detail information groups in a memory in the form combined with the nondeleted common heading information.
Where, therefore, bill form information is processed, it has hitherto been necessary for an operator to supply an information memory with heading information combined with the associated detail information groups, while looking at different bills received or to provide the information memory with a conversion device of complicated mechanism.
Further, with the conventional electronic computer, information supplied almost every day is not immediately processed after being thus converted, but is successively stored beforehand in, for example, a disk type memory. After a certain period, all information received is processed at once, requiring a large capacity memory.